Overview of proposed operations from sea lion?

[phylo_roadking]

I used to live there, until about ten years ago! Unfortunately, before the museum was revamped too...

As far as I can remember, about 150-200 of the 1st Provisional marine battalion...formed in 1941 at Quantico?...was sent early, with the rest of the battalion arriving in 1942 several months after the camp was opened and the U.S. base officially commissioned. Another 250 or so marines arrived before the end of the year. The maximum number ever in the "garrison" was c.750 IIRC.

[flakbait]

How many operational JU-52s and JU-56s were available even in mid Sept `40 and how many men of the German Parachute battalions were available assuming the training command was stripped to the bone to seize a port/ harbor? Losses of men and aircraft would of course likely be horrendous...but seizing that port would be THE decisive action. If they FAIL to seize it intact (USEABLE docks and CLEAR exits), it`s pretty certain it`s GAME OVER...and which ports were to be targeted for seizure ? Provided the weather holds, the Luftwaffe forces the RAF AND RN to withdraw, and can also disrupt the Royal Army build up and preparations while scraping together enough transports AND finally that the German Army can find enough fodder for all their horse powered transport...am seeing more and more why Churchill confidently sent troops and ships to North Africa.

[phylo_roadking]

Flakbait...

How many operational JU-52s and JU-56s were available even in mid Sept `40 and how many men of the German Parachute battalions were available assuming the training command was stripped to the bone to seize a port/ harbor? Losses of men and aircraft would of course likely be horrendous...but seizing that port would be THE decisive action.

...I'm beginning to wonder what use you've made of the many threads on this forum to research the actual plans for Sealion. The FJ were NOT intended to be used for seizing a port in any way at all...http://forum.axishistory.com/viewtopic. ... 3&t=154629 ...except for one element of the operation involving an advance on the rear of the main camp for the defenders of Folkestone. Not actually taking Folkestone itself - that was NOT the kind of operation the FJ were ever intended for at that point in the war.

As for the number of transports available - after the losses in Norway and Holland....plus new builds from Junkers AND crashed aircraft repaired by Junkers, and Fokker in Holland - the number is usually put around 400-410 Ju52s available for Sealion.

As you'll see from the above thread, they were expected to fly a total of THREE successive trips to the UK on S-day alone - two waves to drop the FJ, and a third wave transporting the airborne attack to actually land INSIDE the perimeter at RAF Lympne. So each wave would be likely smaller than the last, when combat losses to fighters and ground fire is taken into account...AND mechanical attrition, although typical German preparation for a large airborne operation was to recall ALL Ju52s to Junkers in the weeks beforehand for factory servicing.

If they FAIL to seize it intact (USEABLE docks and CLEAR exits), it`s pretty certain it`s GAME OVER...

Only in a few locations was it intended to sink blockships; this was discussed recently on another interminable Sealion thread. The British relied on the demolition of quays and cranes; unfortunately, destruction of dockside cranes would not necessarily prevent the relatively rapid reopening of a port, as cargo and vehicles could be unloaded using a cargo ship's own steam cranes. See for example the footage of the DAK being unloaded in North Africa in early 1941.

and which ports were to be targeted for seizure ?

Dover was a target in the first "wide front" 40-division version of the plan....but it was outside the invasion area in the second draft, the 9-division "narrow front" plan...although a variety of "special ops"- type options remained on the table regarding seizing Dover...

Otherwise, the main effort east of Romney Marsh seems to have been seizing Folkestone.

am seeing more and more why Churchill confidently sent troops and ships to North Africa.

"Confidently" might be stretching the point a little. It was a calculated gamble that Sealion wouldn't materialise before the number of tanks sent abroad (the decision was made on the 29th of July IIRC) could be made up by new production out of the factories...

As for the troops actually sent to the Middle East - they were the Australian "short" infantry brigade in the UK and some elements of the NZEF still in the UK that were sent, the latter to join the echelon of the NZ Expedition Force already in Egypt. Apart from the armoured units, the British Army in the UK wasn't weakened in any way

And finally...

Provided the weather holds, the Luftwaffe forces the RAF AND RN to withdraw, and can also disrupt the Royal Army build up and preparations....

Just a minor note really - but NOONE calls the British Army the "Royal Army". Except one disreputable author some of us are acquainted with.

EDIT: P.S., what is a "Ju56"?

[Maxschnauzer]

As far as I can remember, about 150-200 of the 1st Provisional marine battalion...formed in 1941 at Quantico?...was sent early, with the rest of the battalion arriving in 1942 several months after the camp was opened and the U.S. base officially commissioned. Another 250 or so marines arrived before the end of the year. The maximum number ever in the "garrison" was c.750 IIRC.

This account only mentions the 400 strength battallion which embarked in May and the 152 which followed a month later:

Orders quickly followed for a Marine unit to provide security for this "naval operating base" (NOB) and the 1st Provisional Marine Battalion was organized in 1941 at Quantico, under command of Lieutenant Colonel Lucian W. Burnham. His executive officer was Major Louis C. Plain. In preparation, the Marines of that battalion received some rigorous and varied training, because one could not predict what duties their assignments would require of them.

The 400-man battalion left the U.S. in May 1942, on the Santa Rosa, a converted cruise ship of the Italian-American line, headed across the North Atlantic for a destination known to very few. A month later, an augmentation force of 152 enlisted Marines arrived on board the SS Siboney, led by Second Lieutenant John S. Hudson.

http://www.nps.gov/history/history/onli ... 0/sec4.htm

Maybe the Marines presence in NI in December was one of the reasons why the documents now in the hands of the Museum were classified Top Secret.

[phylo_roadking]

I've seen that account too, Max...but as far as I remember now it was actually the rump of the 1st Provisional that was sent in May, the first elements having arrived earlier. The question would be - what was the total complement listed for 1st Provisional as of May - was the total complement 400, or was the "remainder" that was sent bringing the total battalion strength in Derry up to 400 eventually? Or....was the total in Derry after that May consigment of manpower the lead elements plus the 400 sent in May? If you see what I mean by the three possible options in there...

I would have to say, personally, that 400 seems to be a very "short" battalion...? "Provisional" and scratch or not...

Maybe the Marines presence in NI in December was one of the reasons why the documents now in the hands of the Museum were classified Top Secret.

THIS is of course entirely possible too

One further possibility is that the "lead elements" were the Marine complements of any USN escorts that put in at Lisahally...in the early days of its use as a USN patrol base before the February 5th 1942 commissioning.

[Maxschnauzer]

One further possibility is that the "lead elements" were the Marine complements of any USN escorts that put in at Lisahally...in the early days of its use as a USN patrol base before the February 5th 1942 commissioning.

Now this possibility makes a LOT of sense to me. An interesting puzzle, I'll keep digging. As the son of a son of an Ulsterman I find this a fascinating topic. A cursory search in the WWII in Western Europe & Atlantic section turned up nothing pertinent, maybe I should start a thread there.

[flakbait]

Meant JU-86 which was rapidly relegated to transport duties by this stage of the war. And as far as winching off panzers, not if a correct demolition job is done, ie, the remaining part of the damaged pier allows the just unloaded panzer to slide into the harbor. Lastly understand the German paras HISTORIC actual plan to seize an airfield, but even seizing Folkestone, how many panzers can the Luftwaffe land there per day ? That`s correct...ZERO. Was simply applying the theory that at this stage of the war that at least psychologically, the German panzers are the most powerful (and mobile) ground forces available. Get THEM ashore in numbers and suddenly Churchill may be forced to consider an extended vacation in Canada...

[phylo_roadking]

And as far as winching off panzers, not if a correct demolition job is done, ie, the remaining part of the damaged pier allows the just unloaded panzer to slide into the harbor. Lastly understand the German paras HISTORIC actual plan to seize an airfield, but even seizing Folkestone, how many panzers can the Luftwaffe land there per day ? That`s correct...ZERO.

Don't make the same mistake that, for example, the British nearly made at Dunkirk....that the East Mole couldn't be used to embark troops....until they had to try

Any dockside that a ship can draw up against can be used to unload cargo using the ship's own winches...and I'm not aware of any plans to destroy or otherwise render unuseable every single metre of dockside at Folkestone and other ports.

[flakbait]

Point well considered. Plus the German Army combat engineers were rather creative and determined when needed...would guess they would cobble something sufficiently useful together rather rapidly left to their own devices. Once panzers are ashore in numbers...

[Maxschnauzer]

I used to live there, until about ten years ago! Unfortunately, before the museum was revamped too...

As far as I can remember, about 150-200 of the 1st Provisional marine battalion...formed in 1941 at Quantico?...was sent early, with the rest of the battalion arriving in 1942 several months after the camp was opened and the U.S. base officially commissioned. Another 250 or so marines arrived before the end of the year. The maximum number ever in the "garrison" was c.750 IIRC.

BINGO! From the US Marine Corps Handbook 1941-45: Marine Barracks in Derry "established" (not "constructed" but "established") 5 Feb, 1941. I salute you, Sir.
http://books.google.com.ph/books?id=dr0 ... 41&f=false

[LWD]

This site mentions a fairly large contingent on 26 January 1942. However it says soldiers rather than Marnines so I'm not sure if they were army or the author is unfamiliar with the conventions. I'm also not sure just how good the site is:
http://www.examiner.com/article/secret- ... nd-release

[phylo_roadking]

That's just the author of the article conflating events to create a timeline; this...

January 26, 1942 — 4,508 soldiers from 34th Infantry Regiment docked in Belfast.

...refers to the first arrival of U.S. Army personnel in the province. THESE are however more interesting...

June 30, 1941 — 362 civilian technicians arrive in Derry.

August 1, 1941 — US Navy Civil Engineering Corps begin construction work.

...as they confirm the beginning of work on the USN's Lisahally/Ardmore installations many months before Pearl Harbour, of course. I would need to check - but these would fit in with the extension of the PanAmerican Defence Zone most of the way across the Atlantic eventually in 1941 y stages, and the U.S. taking over repsonsibility for the occupation and defence of Iceland...so it would indeed make sense for the USN to have a port facility at the "other" end of the Atlantic convoy routes if they're going to be accompanying vessels "most" of the way across...!

[Maxschnauzer]

That's just the author of the article conflating events to create a timeline; this...

January 26, 1942 — 4,508 soldiers from 34th Infantry Regiment docked in Belfast.

...refers to the first arrival of U.S. Army personnel in the province. THESE are however more interesting...

June 30, 1941 — 362 civilian technicians arrive in Derry.

August 1, 1941 — US Navy Civil Engineering Corps begin construction work.

...as they confirm the beginning of work on the USN's Lisahally/Ardmore installations many months before Pearl Harbour, of course. I would need to check - but these would fit in with the extension of the PanAmerican Defence Zone most of the way across the Atlantic eventually in 1941 y stages, and the U.S. taking over repsonsibility for the occupation and defence of Iceland...so it would indeed make sense for the USN to have a port facility at the "other" end of the Atlantic convoy routes if they're going to be accompanying vessels "most" of the way across...!

I'm still thinking that the Marine detachment serving Embassy duty in London which started out at 60 but was beefed up to 120 before Pearl Harbor, could have possibly sent a couple of squads up north while they were being reinforced "on the QT" to serve as security detail for the bases under construction in early '41 without drawing much attention. Hence the "establishment" of a "Marine Barracks" in Feb '41 while the 1st Provisional Bn was still in the process of being stood up in the States. But that's pure speculation on my part.

[Maxschnauzer]

Here is the official U.S. Navy account of the construction of the Bases in Derry from The Bureau of Yards and Docks of the Civil Engineer Corps:

Base I, Londonderry.

With the advent of war, Londonderry immediately became a port of inestimable value as a base for North Atlantic convoy escorts. These escorts consisted principally of destroyers and lesser craft of the United States, Canadian, and British navies. The essential North Atlantic sea lane had its terminus in ports bordering the Irish Sea in western Scotland and England. As the maintenance of this thin supply line through the ever-tightening German blockade was imperative to the continuance of British resistance, the top priority was given the project of establishing at Londonderry the first United States naval base in the United Kingdom.
Londonderry is situated some 4 miles up the River Foyle, on the northern coast of Ireland. Its location also made it the most suitable port for the allocation of supplies to other projects.

Four miles downstream from the city of Londonderry, and on the opposite bank, an area, known as Lisahally, offered deepwater and adjoining land space sufficient for unloading and storing large quantities of supplies.

A week before the contract was signed in Washington on June 12, 1941, the CEC officer-in-charge arrived in Londonderry to prepare the way for the arrival of contractor's forces and construction materials and equipment.

Many activities were to be scattered within a 4-mile radius of administration headquarters, located in the center of Londonderry. An abandoned shipyard, where the Admiralty had been engaged in the construction of a small slipway and services for that work, became the center of industrial facilities for ship repair. At Lisahally a deep-water unloading wharf, storehouses, and a tank farm were established. Tanker and fueling berths were available along an existing Admiralty jetty. Three personnel areas, to accommodate 6000 men, a 500-bed hospital, an ammunition depot, and a radio station were constructed in the surrounding countryside. In planning the project, considerable emphasis was placed on dispersal as a defense against bombing attacks, which, except for one minor incident, never materialized.
Work on the most pressing projects -- the first of the personnel areas at Beech Hill, the storage area at Lisahally, and the ship-repair facilities -- began in mid-July, when the first ship loaded with tools, equipment, and materials arrived from the States. In September the job expanded to include the second large hut camp at Beech Hill and the administration area. By October, the first pile-driving rigs had been received and assembled, and pile driving was begun for the loading wharf at Lisahally. At the same time, work was in progress on all the major projects except the tank farm, for which materials were a long time in arriving.

With the United States' entry into the war, a new plan of strategy was evolved which materially changed the base-building program in the European theater. Under this program, Londonderry was commissioned as a naval operating base. Notable additions were a 750-foot extension to the 1000-foot loading wharf at Lisahally and enlarged radio installations. The size of the hospital was reduced from 500 to 200 beds.

By the first of the year, work was being pressed to the utmost in spite of the almost incessant rainfall and the much-shortened daylight period characteristic of northern latitudes. Almost 600 Americans and a considerably larger number of Irishmen were employed. In January, most of the magazines in Fincairn Glen were completed, and the first materials for the new warehouses arrived at Lisahally.

With the Navy's efforts in European waters centered on escorting convoys, not only to Britain but also to Murmansk, as American aid to Russia was increased. Londonderry promised to remain essential to the fleet and there was not question of relinquishing its control to the British.

Londonderry was commissioned as a naval operating base on February 5, 1942, the first outpost of the Navy's shore establishment in the European theater. The first American warship had arrived in December 1941. As enlisted personnel arrived, facilities were placed in operation as quickly as they were usably complete. By February 22, many of the ship-repair facilities and shops were being readied for use; by March 3, the first major group of United States naval personnel had arrived and were quartered in the barracks at Springtown.

Much of the original work remained to be done and base operations were constantly expanding, which allowed no let-up in construction activity. By the middle of April, both the hospital at Creevagh and the ammunition depot had been substantially completed. By May 1, work in the industrial area was completed, and a week later the new extension to the loading wharf at Lisahally was ready for use.

As the remaining major projects moved rapidly to completion, the attention of the contractor's force was shifted to maintenance, and many skilled workmen were released for transfer to projects in progress in Scotland. The tank farm, begun in April, had been continually delayed by the difficulty in obtaining materials from the United States. However, this did not materially handicap the activity, as the delay had been anticipated and adequate supplies of oil from British sources had been made available. Operating activities along the waterfront were then at a peak in preparation for the invasion of North Africa.

A 250-man addition to the barracks at the Lisahally storage area, approved in August 1942, was completed on September 5. Londonderry ceased to be the focal point of construction effort, and headquarters of the officer-in-charge were moved to Helensburgh, Scotland, where the Dumbartonshire pipeline was the last major project to be constructed under the CPFF contract. A small local office was left in Londonderry, to supervise the force of 1,000 men handling base maintenance and the remaining construction.

During the course of the civilian contract at Londonderry, a great naval base had been constructed and put into operation. The work, dispersed over an area of 426 acres, included 1,350 separate buildings, of which 55 were structures either 40 by 100 feet or 60 by 90 feet; more than 90,000 square feet of wharfage; construction and paving of more than 12 miles of roadway; 12 miles of water pipe; 8 miles of drainage ditches; 20 miles of electric cable; 27 miles of fencing; electric generators; and 11 radio masts. In addition, a tank farm for storage of fuel and diesel oil had been erected.

Hindered by mud, rain, and the swampy banks of the River Foyle, the contract force, and later the Seabees, often waited in vain for materials and equipment. An innovation was the prefabricated type of building shipped from the United States, including the newly devised quonset huts. Long-span frames were used not only for warehouses and shops, but also for the theaters and recreation buildings; the huts served as living quarters, hospitals, and offices.

http://www.ibiblio.org/hyperwar/USN/Bui ... es-19.html

[sitalkes]

If you would like to see a quick Powerpoint presentation on Sealion, try these: https://drive.google.com/file/d/0B_JIBY ... lJ3ZjJqdUU - the whole presentation, including the barges ( about 500 Mb)
https://drive.google.com/file/d/0B_JIBY ... 0Y1Z0tSYjg - the invaders
https://drive.google.com/file/d/0B_JIBY ... WJsMTI1MUk - the defenders
(sorry, the commentary cuts out because it isn't finished yet)

When discussing the harbours, remember that orders were issued to only cause destruction that could be fixed after a week, as the British commanders expected to get the harbours/bridges, etc back under their own control pretty quickly. Also note that Newhaven, which had a larger capacity than Folkestone in 1940, is never counted in the capacity calculations. Rye also had a commercial wharf that supported a cross-channel steamer service and could have made a small contribution, but is not mentioned. Another port that might have been useful to the Germans is the Downs (off Deal) which at one time was the busiest port in England.

If you want a to read the British point of view, read Brian Lavery's well written and fully referenced "We Shall Fight them on the Beaches". It includes lots of background information and has no assumed knowledge. Peter Schenk's book is the best to get information about the German forces. If you want to wargame it, try Decisive Campaigns: The Blitzkrieg from Warsaw to Paris. http://www.matrixgames.com/products/390 ... w.to.Paris. You can see the initial planned Sealion deployment map using that game at http://www.matrixgames.com/forums/tm.asp?m=3594443. For a fun tactical level game, try Battle Academy http://www.slitherine.com/games/bbc_ba_pc which has a series of very good Sealion scenarios.